There are a lot of reasons that people in other countries are not cozy with the United States.
Here is one minor example of why.
The problem here is drill bits, or rather, describing the diameter of drill bits. The rest of the world uses the metric system, which is simpler than whatever it is that we're using.
Here's the assortment of bits: 1/16th of an inch; 5/64ths; 3/32nds; 7/64ths; 5/32nds; and 3/16ths. Using this method requires thinking about common denominators, admittedly not a tough mathematical problem, for the most part.
Seven 64ths of an inch is one 64th from being 1/8th of an inch. Three 32nds is one 32nd from 4/32s, or 1/4th of an inch. What's the difference between 5/32nds and 3/16ths? One 32nd of an inch. Why not make all of the bits in 32nds? Too simple.
In the metric system, the same set is 1.59 millimeters; 2 millimeters, 2.38 mm; 2.8 mm; 3.18 mm, 3.97 mm and 4.8 mm. There are 25.4 mms in 1 inch. So 2.38 mm is a little less than 1/10th of an inch, which we call 3/32 of an inch. Which is a little less than 1/10th of an inch.
Can't we at least use 10ths of inches? Instead of using odd little increments like 5/32s?
Or, you can ignore the whole thing and just eyeball which bit you want. Then a few weeks later your shelves fall off the wall.